Functional skin patches or sensor plasters for medical or industrial monitoring networks provide limited space in a thickness direction and further require flexibility to fit to the underlying body, e.g. a human body. In case a thermo harvester is integrated in a functional skin patch, a radiating surface of maximized area is desirable to enhance the thermal conductivity between the functional skin patch and the surrounding air. To provide a low thermal transfer resistance of the outer surface of the functional skin patch, a metal layer may be provided. However, in case the functional skin patch is equipped with an antenna unit, the radiating outer surface and the antenna part compete for the surface area of the outer surface of the functional skin patch.
It is an object to provide a functional skin patch having an antenna and improved thermo harvesting properties.